1. Field of the Invention
The present invention relates to an image forming apparatus that performs a control corresponding to a type of sheets for use.
2. Description of the Related Art
Heretofore, as an image forming apparatus, there has been known an image input/output processing apparatus which is generally called as a digital multifunctional apparatus, has a copier function, a printer function, and further, a facsimile function and the like, and is capable of executing multiple image processing.
The image forming apparatus is capable of printing by using a variety of sheets such as plain paper, thick paper, coated paper, recycled paper, colored paper and a transparency (OHP sheet). The image forming apparatus has a construction capable of performing image formation under appropriate process conditions corresponding to types of the respective sheets.
For example, a printing apparatus described in Japanese Patent Application Laid-Open No. 2002-086860 decides, according to the selected type of sheets, offset data regarding a transfer voltage at the time of transferring toner images to the sheets. In such a way, an appropriate printing result is obtained.
In recent years, along with an increased variety of such recording mediums, not only such a sheet type as the plain paper but also a specific sheet brand is designated, and the printing can be performed under the optimum conditions for the sheet brand. A device controller that controls the image forming apparatus has a sheet database that stores attribute data of the sheets which the image forming apparatus supports. For example, an image forming apparatus described in Japanese Patent Application Laid-Open No. 2005-316336 is provided with a function to allow a user to set a variety of parameters for the image formation for each of the sheet types.
The parameters may include not only parameters such as a transfer condition and a fixation condition in image formation of an electrophotographic process, which are related to the image formation, but also a variety of parameters such as sheet feeding condition in a sheet feeding device and a condition for curl correction in a sheet delivering device.
There is a variety of methods regarding display of sheet information registered in the sheet database. For example, in the invention described in Japanese Patent Application Laid-Open No. 2004-240585, there is disclosed a technology of not displaying the registered sheet information entirely as a list but displaying the sheet information based on use conditions by the user. Supportable sheet types can be added to the database.
In the case where the user adds new sheets without removing sheets already stored in the sheet feeding device, and sets a sheet type different from a type of the already stored sheets, the following phenomena have occurred.
(A) Even if parameters corresponding to the already stored sheets are not suitable as image formation parameters of the newly set sheet type, image forming processing is carried out according to the designated parameters.
(B) In the case where an operator sets a different sheet type though the type of the newly added sheets is the same type as that of the already stored sheets, appropriate image formation is not performed.